The present invention relates generally to devices which are implanted within the body of a living animal or human to impart a therapeutic benefit to a target tissue. More particularly this invention relates to a device and method for selectively electrically stimulating body tissues or organs and also for selectively delivering a medicament to a target tissue or organ. It is also the intention of this invention to provide improved treatment by reducing the time between the sensing of a specific activity within the tissue or organ being treated and the onset of the delivery of the electrical stimulus or medicament drug to the site of the sensed activity.
Many disorders, e.g., brain disorders and certain types of paralysis, are treated by an electrical stimulus or local drug delivered to specific sites in the brain or the body. One shortcoming of conventional treatment devices and procedures is that conventional treatment devices are large and their placement may cause damage to the patient. Another shortcoming of conventional treatment devices and procedures is that the devices are often implanted and must remain connected to the outside world for their control signal or energy supply. Another shortcoming of conventional devices and procedures is that drug delivery to the target tissue may cause trauma to the patient and may not be precisely delivered to the target tissue. Another shortcoming of conventional procedures is that the physical connection to the outside world and the repeated trauma to the patient required by repeated invasion and introduction of foreign objects into the tissue increases the likelihood of infection. Yet another shortcoming of conventional devices and procedures is that they do not provide precise timing of the delivery of the electrical stimulus or drug in response to phenomena happening in, and to stimuli generated by, the tissue or the organ being treated indicating the need for the delivery of such an electrical stimulus or drug.
It is an object of this invention to provide an apparatus and method of selectively applying an electrical stimulus over a period of time to a target tissue of the body, e.g., the brain, without creating a large lesion in the target area and without requiring a connection to the outside world, i.e., outside the patient""s body. A selective stimulus means a stimulus is specific in time and geometry and may be triggered by tissue activity at the specific location.
It is another object of this invention to provide an apparatus and method for selectively delivering a medicament over a period of time to a target tissue of the body, e.g., the brain, without creating a large lesion in the target area and without requiring a connection to the outside world, i.e, outside the patient""s body.
It is yet another object of this invention to provide a method of treating body tissue, comprising the steps of preparing a device capable of generating electrical current at a therapeutic voltage and amperage in response to ultrasonic vibrations; disposing the device in the vicinity of the tissue to be treated; and subjecting the device to ultrasonic vibrations in an amount and for a period of time sufficient for the device to generate electrical currents at a therapeutic voltage and amperage.
It is a further object of this invention to provide a device for treating body tissue, comprising a housing provided with a medicament storage compartment. An oscillating member is attached to the housing and communicates with the medicament storage compartment and is adapted to oscillate in response to ultrasonic stimulation. A medicament port is disposed on the housing and is in fluid communication with the medicament storage compartment and is adapted to permit a medicament to be introduced into and contained in the compartment. The medicament port is further adapted to selectively release the medicament from the medicament storage compartment in response to the oscillations of the oscillating member which produce a xe2x80x9cpumpingxe2x80x9d action to pump the medicament out of the compartment in response to external high frequency stimulation.
It is still a further object of this invention to provide a method of treating body tissue, comprising the steps of preparing a device comprising a housing provided with a medicament storage compartment. An oscillating member is attached to the housing and is in fluid communication with the medicament storage compartment and is adapted to oscillate in response to ultrasonic stimulation. A medicament port is disposed on the housing and communicates with the medicament storage compartment and is adapted to permit a medicament to be introduced into and contained in the compartment. The medicament port is further adapted to selectively release the medicament from the medicament storage compartment in response to oscillations of the oscillating member. In operation, a medicament is introduced through the medicament port and into the medicament storage compartment. The device is disposed in the vicinity of the tissue to be treated and is subjected to ultrasonic vibrations in an amount and for a period of time sufficient for the oscillating member to oscillate in an amount and for a period of time to cause the desired quantity medicament to be discharged from the medicament storage compartment through the medicament port to the tissue to be treated.
It is yet another object of this invention to provide a sensor or an array of sensors communicating with a tissue or organ being treated, e.g., the brain. The sensors communicate with one or more actuators adapted to selectively deliver a predetermined amount of an electrical impulse or a medicament to the tissue or organ being treated in response to the sensed stimulus generated by the tissue or organ being treated indicating the need for the delivery of such an electrical impulse or medicament. In an especially preferred embodiment, the stimulation is sensed in one tissue, e.g., the brain or a nerve and the stimulation occurs in a different tissue, e.g., a paralyzed leg muscle.